1. Field of the Invention
The present invention relates to an image forming apparatus and method thereof, and, more particularly, to an image forming apparatus that limits the amounts of toner of a plurality of colors, and the method thereof.
2. Description of the Related Art
When a color printer generates an image, color representation is normally performed by means of toner, ink, and so forth in four colors, which are cyan (C), magenta (M), yellow (Y), and black (K). In this case, although color representation is possible up to a Duty of 400% in which toners in all four colors (recording agent) are mixed at 100%, when data with such a high Duty are printed, the print paper winds around the fusing unit due to the large amount of toner, thereby rendering normal printing impossible. Further, a drop in image quality also results when printing is performed such that so-called blurring caused by the scattering of toner, is generated, and therefore fine lines and the like run.
Processing known as so-called undercolor removal, black generation, and so forth, to limit the amount of toner in order to prevent this phenomenon, has been performed. Such processing enables a reduction in the amount of toner in all four colors to about 230%.
In addition, there is a risk of the recording medium absorbing ink when data with this high Duty is printed. Therefore, conventionally, processing to reduce the sum of total of the amounts of recording agent in a single uniform fashion without changing the proportion of each cyan, magenta, and yellow component is also carried out (Japanese patent application No. 2608262, for example)
However, the generation of blurring due to the type of printer cannot be prevented by means of undercolor removal and black generation alone, and a drop in image quality cannot be prevented unless the Duty of the whole amount of toner in four colors is reduced to about 150%, for example.
Meanwhile, when the Duty is limited (to about 150%, for example) in a single uniform fashion, because brightness inversion is generated in dark areas and the color reproduction range is then small, deterioration in the picture quality results.